TABLE 2.
Association between maternal GCK rs1799884 genotype and maternal glucose levels in pregnancy
| Total N | Mean ± SE plasma glucose level by GCK rs1799884 genotype |
Effect size ± SE per T-allele (mmol/l)*† | P† | |||
|---|---|---|---|---|---|---|
| CC | CT | TT | ||||
| FPG (mmol/l) | ||||||
| European | 3,811 | 4.55 ± 0.01 | 4.59 ± 0.01 | 4.63 ± 0.03 | 0.03 ± 0.01 | 0.001 |
| Thai | 1,706 | 4.42 ± 0.01 | 4.51 ± 0.02 | 4.52 ± 0.08 | 0.08 ± 0.02 | <0.0001 |
| 1-h plasma glucose (mmol/l) | ||||||
| European | 3,811 | 7.39 ± 0.03 | 7.54 ± 0.05 | 7.69 ± 0.15 | 0.15 ± 0.05 | 0.001 |
| Thai | 1,706 | 8.25 ± 0.05 | 8.35 ± 0.09 | 8.54 ± 0.37 | 0.11 ± 0.09 | 0.24 |
| 2-h plasma glucose (mmol/l) | ||||||
| European | 3,811 | 6.11 ± 0.02 | 6.12 ± 0.04 | 6.18 ± 0.11 | 0.02 ± 0.04 | 0.56 |
| Thai | 1,706 | 6.61 ± 0.04 | 6.85 ± 0.08 | 6.81 ± 0.30 | 0.21 ± 0.07 | 0.005 |
The European plasma glucose levels by genotype are the mean values across all four field centers. These are presented separately in supplementary Table 1.
*The T-allele of GCK rs1799884 is associated with raised fasting glucose in nondiabetic, nonpregnant populations. The T-allele frequency ranged from 17.1 to 18.7% in the European ancestry samples and was 10.3% in the Thai samples.
†The effect sizes and P values are from linear regression of maternal glucose level against genotype (coded 0, 1, or 2 T-alleles), with field center (European ancestry only), age, BMI, and mean arterial pressure as covariates. Age, BMI, and mean arterial pressure were measured at a median of 28–29 weeks' gestation, depending on the field center. Mean ± SE values are adjusted for these three covariates. FPG, fasting plasma glucose.